| Open tubular capillary electrochromatography (OT-CEC) is a comparatively straightforward approach for capillary electrochromatography (CEC) since the stationary phase is attached to the inner wall of the column, and does not require the fabrication of any frits. The preparation of the stationary phase is critical for OT-CEC. Chitosan (CS) has good physical, chemical and biological characteristics, so there are many reports on its application and modification. But there were few papers about the applications of chitosan and its derivatives on OT-CEC. In this thesis, two chitosan derivatives were synthesized to meet the demand of OT-CEC. And they were used as stationary phase materials for OT-CEC. Their characterizations of the open tubular column were also investigated. Then the columns were used in the separation for the analysis of pharmaceutical compounds. New ideas were provided for the application of chitosan derivatives as well as the stationary phase selection.There are four chapters in this thesis and the main contents are listed as follows:In the first chapter, there is a review, including the principle of CEC, the types of the columns and stationary phase, as well as the nature, the modification and the application of the chitosan and its derivatives. The content and significance of this thesis were also informed.In the second chapter, o-cyanoethylchitosan was synthesizede, and then was used to the preparation of an o-cyanoethylchitosan chemically bonded open tubular column. O-cyanoethylchitosan was characterised by infrared spectroscopy and UV spectra. The optimization of the column preperation conditions, the morphology of the column, the electroosmotic flow performance, the separation performance, the reproducibility and stability were investigated. As the result, the relative standard deviations (RSD) of the electroosmotic flow (EOF) were less than 3.4%. The four nucleotides were separated well, with the efficiencies in the range of 37,000-140,000 plates/m.In the third chapter, the o-cyanoethylchitosan chemically bonded open tubular column was prepared and applied in the analysis of cefoperazone, cefuroxime, cephalothin, cephalosporin, cefixime. The chromatographic conditions were optimized. The column was also applied to the separation of four cephalosporins in milk. Baseline resolution of the studied cephalosporins could be achieved within 14 min. The calibration curves of cefixime, cephalothin, cefuroxime and cefoperazone were linear over the concentration range of 0.6-50 μg/mL,0.8～50 μg/mL, 0.8～50 μg/mL and 1.0～50μg/mL, respectively. The detection limits (S/N =3) of four cephalosporins were ranged from 0.2 to 0.4 μg/mL and the recoveries of milk samples were about 82.0～96.7%(RSD< 3.8%).In the fourth chapter, cyclodextrin-graft-chitosan sol-gel open tubular column was prepared. It was characterised by infrared spectroscopy and X-ray diffraction. The preparation conditions and performance of the column were investigated. Then the column was applied to the separation of xanthopterin isomers and the four phenoxy acid herbicides with similarity structure.Three types of open tubular column were compared. As the result, the sol-gel cyclodextrin-graft-chitosan open tubular column performance best with the highest efficiency for separating xanthopterin isomers and herbicides, which is because its special molecular structure. The efficiencies were in the range of 55,000-68,000 plates/m and 135,000-160,000 plates/m respectively. |
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